Safety tool-retainer.



s. s.v ROBERTS.

SAFETY TOOL RETAINER.

APPLICATION-F1LED JUNE 3,1914.

FIGA.

FIG.;

APatented,June15,1915. i

SAMUEL ROBERTS, OF PITTSBURGH, PENNSYLVAIA.

SAFETY TooLEETArNEE.

Specification of Letters Patent.

Patented June 15, 1915.

Applicationfiled June 3, `1914. Serial No. 842,716.

To all 'whom t may concern? I Be it known that I, SAMUEL S. ROBERTS, a citizen.v of the' United States, residing at Pittsburgh,in` the countyof Allegheny and State of Pennsylvania, have invented a new and useful Safety Tool-Retainer, ofwhich the following is a specification.

My invention relates tothe construction of pneumatic hammers, pneumatic drills, and similar pneumatic tools havingcutters, drills, rivet snaps, etc., removably Secured thereon or thereto, andthe invention-more particularly relates to the constructlonof means for maintaining such tools 1n position Ysus in the tool socket during the operation of the hammer or drill.

One object cf my invention is to'provide a safety tool retainer having novel means whereby the tool shank is engaged and movably secured in retaining the tool in place in the socket of pneumatic hammers, drills and liketools which employ gaseous fluid pressure, such as air and steam, as the motive fluid.

vide a tool retainer having novel means for fastening the tool shank which enables the quick re lacement and removal of the tools.

Still rther objects of the invention will become apparent as the invention `is more fully' described hereinafter and pointed out in the appended claim.

Referring to the drawings forming part of this specification, Figure 1 is a plan of a pneumatic hammer, partlyv in section, the section being taken on the line I-I .of Fig. 5, having a tool retainer constructed vand arranged and applied for use thereon in accordance with my invention. Fig. 2 is a detail plan` of one-half of the sectional bushing employed in securing the tool in the tool socket of the hammer. Fig. 3 is a sectional plan of the tool end of the pneumatic hammer, the section being taken on the line III-III of Fig. 4. "Fig, 4 is a transverse section, taken on the line IV-IV of Fig. 3, showing the end of the hammer cylinder.

Fig. 5 is a similar transverseV sec'tion, the4 section being taken on the line V-V 0f Fig.

'3, showing the end of the tool retaining bushing.

In the accompanying drawings,vin"which` my invention is shown as applied to a pneu.- matic hammer, the numeral 2 designates the hammer cylinder or'ba'rrel having a lengthwise extending bore 3 containing .the re- Another object of my invention is to pro-f ciprocatory piston 4. y The 'cylinder is pro- Vvided Von oneend with a handle 5 -of the usual construction and the other end is provided 'with a counterbore or recess forming a socket 6.f The socket 6 has a counterbore oflarger diameter to receive the two sections of the split bushing 7 forming part of the tool retaining mechanism.

vThe valve mechanismand the Vvalve operating mechanism in the handle of the ham- .der 2 in the usual known manner. The face or outer end of the rivet snap 10 is provided -with a cup-shaped recess 13 which ,in cross section has 'the contourof theheads of the rivets formed with the hammer.

When a chisel or other cutting tool is used with the pneumatic hammer, or when my invention is applied for use in securing drills on the reciprocating pistonn of a pneumatic or steam drill, the shank of such tools will be formed with the reduced portion 11 and enlargement or collar 12, in the manner shown, as will be readily understood.

Secured in the counterbore of the socket 6 isthe sectional bushing 7 which is divided l on its 'diametral center to make two symmetrical halves. AThe bushing 7 has a central opening. 14 of a diameter the same or very slightlyvlarger than that of the shank 11 of the rivet snap or other tool. The fia-nge 15 of the bushing7 is made hexagonal or issquared to receive a wrench or other turning tool in applying the bushing in place.

Inl the end of the hammer cylinder 2, at one side ofthe counterbore, is a'small hole 16 which extends lengthwise parallel with theV bore 3 of the cylinder, andwhich is counterbored, its outer end being vclosed with a screw threaded plug 17. The plug is provided with an axially central `opening and projecting through the hole is a pin' positioned within the counterbored portion of the hole 16 with one end in engagement with the jog forming the bottom of the counterbore and the other engaging with the collar 19 on the pin 18 so as to normally hold the pin in extended position. The outer end ofthe pin 1S`is arranged to project into a registering hole 21 in the ilange of one section of the split bushing 7 this hole being'po'sitioned to receive the pin 18 l,when the bushing7 is in tool holding posiltion in the end of the hammer cylinder 2. Thecounterbore forming the socket 6, at

an intermediate point in its length, is provided with an annular recess 22, and this recess is connected by two slots or recesses 23, 23, (see Fig. 4) in the walls of theI recess forming the socket, these recesses. be ing arranged to extend lengthwise parallel withvand on diametrally opposite sides of ghe lengthwise center ofthe hammer cyliner v2.

' The bushing 7 has'shoulders 24, onebeing provided on each side of each section of theI bushing, which are arranged to enter the annular recess 22 in the wall of the counterbore or socket 6 through the parallel slots 23 extending -rom the end of the hammer into the annular recess22, so that A when the split bushing 7 is applied to the hammer. cylinder to hold therivet snap 10 in place, by moving the bushing 7 a quarter lturn the lugs 2 4 on the bushing sections be-` .come seated in the annular recess 22 so as to be in holding position, andv by engagement with the collar 12 on the end of the 4 shank 11 of the tool, prevent unseating or removal of the tool from the hammer.

In constructing rivet snaps and other tools for use with my improved tool retainer, the shank-11 thereof is made of'suoh length that the collared end 12 thereof will engage with the jog or shoulder defining the bottom of the counterbored recess forming the socket 6 and will hold the ace 25 on the rivet snaps or other tool so that it.does not at any time engage withl they adjacent face of thebushing 7 in the operation'o the hammer, this construction materially re ducing liability of breakage of the tools in service.

1n assembling the parts, the two halves of the bushing 7 areeplaced in position on the shank 11 of the rivet snap or other tool and the bushing while encircling the shank is then insertedin the recessed end or/socket 6 ofthe hammer cylinder, the lugs 24 on the inner end of the bushing section s being positioned within the recess 22 opposite the I Y inner ends of the parallel slots 23 which nieaees are located in opposite sides of the socket 6. Afterl the bushing 7 is placed in such position it is given a quarter turn which moves the lugs 24.- out ofa position registerv ing with, the inner end of the parallel recesses 23 intoy a position between these recesses. The spring `pressed' pin 18 in the socket end of the hammer cylinder then i moves outwardly to extend'into the hole 21 in the bushing, and acts to prevent turning of the bushing 7 until it is desired to reniovethe tool and bushing. When it is desired to remove the split bushing7, in order to replacethe rivet snap 10 with another,l or with a different type of tool, a pin oi' `suitable size is pushed into the hole 21 in the bushing 7 so as to depress the pin 18 in the socket end of the hammer until its outermost end is in line with the joint between the adjoining faces .of the iange 15 on the bushing and the face of the end of" the hammer. When in this position the. bushing r7 is readily turned until the lugs 211 register' with the slots '23 and the bush- .'ing and tool ,are then removed endwise.-

The advantages of my invention, which will be apparent .to those skilled in the art, arise from the simplicity of my improved tool retaining mechanism and the ease with The combination with a hollow body having internal -longitudinal slots extending from one end and terminating in an internal annular groove, of a tool holder including seg-mental portions forming a cylindrical body when assembled, each. of said portions having a projectionY thereon adapted to move along one of the slots and be turned into the groove, and a tool having a shank embraced by the holder and provided with a lateral enlargement for engagement with the inner end `of the tool holder to prevent displacement of the tool.

4 In testimonywhereof, l have hereunto set my hand. c

SAMUEL S; ROBERTS. Witnesses:

. J. CLYDn MILLER,

Jnmcs C. .I-IAMRooK.` 

